1. Field of the Invention
The present invention relates in general to the field of dentistry. More particularly, the present invention relates to a dental chair headrest and a dental chair that includes the headrest. Specifically, a preferred embodiment of the present invention relates to a dental chair that can be folded flat and which includes a headrest defining a void through which a prone patient's nose and mouth can protrude and be reached from below by the dentist. The present invention thus relates to dental apparatus and methods of the type that can be termed prone.
2. Discussion of the Related Art
Within this application several publications are referenced by arabic numerals within parentheses. Full citations for these, and other, publications may be found at the end of the specification immediately preceding the claims. The disclosures of all these publications in their entireties are hereby expressly incorporated by reference into the present application for the purposes of indicating the background of the present invention and illustrating the state of the art.
Historically, it has been known in the field of odontology to seat a patient in a chair designed to facilitate dental treatment. Prior art dental chairs of the type hereunder consideration, sometimes called examination chairs, are well-known to those skilled in the art. A conventional dental chair is typically used to facilitate dental prophylaxis. For example, a patient will typically be reclined in a conventional seated posture and a dentist will sit to one side, and behind, the patient.
However, with regard to this conventional seated posture, the dentist is required to lean over the patient's oral cavity in order to provide treatment..sup.(1,2) This approach has been ergonomically inefficient because stress is induced in the neck and back of the dentist. The more time spent by the dentist leaning over the patient's oral cavity, the greater is the stress on the neck and back. If a long period of time is required to perform a procedure, or if more than just a few patient's are to be treated during the day, the stress on the neck and back can accumulate to a level that is uncomfortable for the dentist. This can result in fatigue, thereby possibly lowering the quality of treatment provided by the dentist. In a severe case, the fatigue can accumulate to a level that cannot be tolerated by the dentist. Thus, a previously recognized problem has been that leaning over the patient results in neck and back stress being incurred by the dentist leading to decreased efficiency. Needless to say, it is desirable to provide an arrangement having higher efficiency. What is needed therefore is an apparatus and method that efficiently positions a patient for more efficient dental treatment.
One prior art approach, in an attempt to solve the fatigue problem referred to above, involves stopping treatment to permit the dentist to take a break. However, providing dental treatment is a competitive business. A preferred solution will be seen by the end-user as being cost effective. Therefore, what is also needed is an apparatus and method that efficiently positions a patient and is cost effective. A solution is cost effective when it is seen by the end-user as compelling when compared with other potential uses that the end-user could make of limited resources.
Another previously recognized problem has been that debris created by dental treatment can fall down a patient's throat. Such events can more likely happen during certain procedures such as, for example, upper fillings and root canals. Therefore, what is also needed is an apparatus and method that helps to prevent debris entering a patient's throat.
One prior art approach, in an attempt to solve the debris problem referred to above, involves providing a vacuum nozzle within the patient's oral cavity. However, a disadvantage of this previously recognized approach is that not all debris is gathered by such a vacuum nozzle. Another disadvantage of this previously recognized approach is the vacuum nozzle can become obstructed by a solid object, such as the tissue of the patient's gum or inner cheek.
Another previously recognized problem has been that the effect of local anesthetics appears to be, at least in part, a function of the ambient gravitational field, as evidenced by spatially resolved differential block..sup.(3,4) Therefore, what is also needed is an apparatus and method that will permit the dentist to more fully adjust the patient's posture with regard to the gravitational field. Heretofore the above-discussed requirements have not been fully met.
The below-referenced patents disclose embodiments that were at least in-part satisfactory for the purposes for which they were intended. The disclosures of all the below-referenced prior United States patents in their entireties are hereby expressly incorporated by reference into the present application for purposes including, but not limited to, indicating the background of the present invention and illustrating the state of the art.
U.S. Pat. No. 5,233,713 discloses a head holder for nuclear imaging. U.S. Pat. No. 5,177,823 discloses an adjustable headrest. U.S. Pat. No. 4,823,776 discloses an adjustable head support. U.S. Pat. No. 4,333,638 discloses a massage table having a removable headrest. U.S. Pat. No. 3,897,102 discloses a chair with a face hole that is adjustable to a flat configuration. U.S. Pat. No. 2,631,303 discloses a portable folding cot with a face hole. Canadian Patent 1,061,219 discloses a head support. French Patent 553.787 discloses a surgical table having a head rest with a hole.